Mathematica Referring to elements of a table in Mathematica

I have a table that I've named B. And I want to create table that is essentially the change in values of B. If I was writing this on paper I would say: Let ##b_i \in B##, for ##0\leq i\leq100##. Then let ##c_i \in C## such that ##c_i= b_{i+1}-b_{i}##. I don't know how to say that in Mathematica's language though.

Another option I guess would be to find a way to assign an indexed variable to each value of the table. With the indexing variable being the same.